/*
Copyright (C) 1996-1997 Id Software, Inc.

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 3
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/
// net_main.c

#include "quakedef.h"

#pragma comment (lib, "ws2_32.lib")


qsocket_t	*net_activeSockets = NULL;
qsocket_t	*net_freeSockets = NULL;
int			net_numsockets = 0;

BOOL	tcpipAvailable = FALSE;

int			net_hostport;
int			DEFAULTnet_hostport = 26000;

char		my_ipx_address[NET_NAMELEN];
char		my_tcpip_address[NET_NAMELEN];

void (*GetComPortConfig) (int portNumber, int *port, int *irq, int *baud, BOOL *useModem);
void (*SetComPortConfig) (int portNumber, int port, int irq, int baud, BOOL useModem);
void (*GetModemConfig) (int portNumber, char *dialType, char *clear, char *init, char *hangup);
void (*SetModemConfig) (int portNumber, char *dialType, char *clear, char *init, char *hangup);

static BOOL	listening = FALSE;

BOOL	slistInProgress = FALSE;
BOOL	slistSilent = FALSE;
BOOL	slistLocal = TRUE;
static double	slistStartTime;
static int		slistLastShown;

static void Slist_Send (void *);
static void Slist_Poll (void *);
PollProcedure	slistSendProcedure = {NULL, 0.0, Slist_Send};
PollProcedure	slistPollProcedure = {NULL, 0.0, Slist_Poll};


sizebuf_t		net_message;
int				net_activeconnections = 0;

int messagesSent = 0;
int messagesReceived = 0;
int unreliableMessagesSent = 0;
int unreliableMessagesReceived = 0;

cvar_t *net_messagetimeout;
cvar_t *hostname;

BOOL	configRestored = FALSE;


// these two macros are to make the code more readable
#define sfunc	net_drivers[sock->driver]
#define dfunc	net_drivers[net_driverlevel]

int	net_driverlevel;


double			net_time;

double SetNetTime (void)
{
	net_time = Sys_DoubleTime ();
	return net_time;
}


/*
===================
NET_NewQSocket

Called by drivers when a new communications endpoint is required
The sequence and buffer fields will be filled in properly
===================
*/
qsocket_t *NET_NewQSocket (void)
{
	qsocket_t	*sock;

	if (net_freeSockets == NULL)
		return NULL;

	if (net_activeconnections >= svs.maxclients)
		return NULL;

	// get one from free list
	sock = net_freeSockets;
	net_freeSockets = sock->next;

	// add it to active list
	sock->next = net_activeSockets;
	net_activeSockets = sock;

	sock->disconnected = FALSE;
	sock->connecttime = net_time;
	Q_strcpy (sock->address, "UNSET ADDRESS");
	sock->driver = net_driverlevel;
	sock->socket = 0;
	sock->driverdata = NULL;
	sock->canSend = TRUE;
	sock->sendNext = FALSE;
	sock->lastMessageTime = net_time;
	sock->ackSequence = 0;
	sock->sendSequence = 0;
	sock->unreliableSendSequence = 0;
	sock->sendMessageLength = 0;
	sock->receiveSequence = 0;
	sock->unreliableReceiveSequence = 0;
	sock->receiveMessageLength = 0;

	return sock;
}


void NET_FreeQSocket (qsocket_t *sock)
{
	qsocket_t	*s;

	// remove it from active list
	if (sock == net_activeSockets)
		net_activeSockets = net_activeSockets->next;
	else
	{
		for (s = net_activeSockets; s; s = s->next)
			if (s->next == sock)
			{
				s->next = sock->next;
				break;
			}

		if (!s)
			Sys_Error ("NET_FreeQSocket: not active\n");
	}

	// add it to free list
	sock->next = net_freeSockets;
	net_freeSockets = sock;
	sock->disconnected = TRUE;
}


static void NET_Listen_f (void)
{
	if (Cmd_Argc () != 2)
	{
		Con_Printf (PRINT_DEFAULT, "\"listen\" is \"%u\"\n", listening ? 1 : 0);
		return;
	}

	listening = Q_atoi (Cmd_Argv (1)) ? TRUE : FALSE;

	for (net_driverlevel = 0; net_driverlevel < net_numdrivers; net_driverlevel++)
	{
		if (net_drivers[net_driverlevel].initialized == FALSE)
			continue;

		dfunc.Listen (listening);
	}
}


static void MaxPlayers_f (void)
{
	int 	n;

	if (Cmd_Argc () != 2)
	{
		Con_Printf (PRINT_DEFAULT, "\"maxplayers\" is \"%u\"\n", svs.maxclients);
		return;
	}

	if (sv.active)
	{
		Con_Printf (PRINT_DEFAULT, "maxplayers can not be changed while a server is running.\n");
		return;
	}

	n = Q_atoi (Cmd_Argv (1));

	if (n < 1)
		n = 1;

	if (n > svs.maxclientslimit)
	{
		n = svs.maxclientslimit;
		Con_Printf (PRINT_DEFAULT, "\"maxplayers\" set to \"%u\"\n", n);
	}

	if ((n == 1) && listening)
		Cbuf_AddText ("listen 0\n");

	if ((n > 1) && (!listening))
		Cbuf_AddText ("listen 1\n");

	svs.maxclients = n;

	if (n == 1)
		Cvar_SetValue (deathmatch, 0);
	else Cvar_SetValue (deathmatch, 1);
}


static void NET_Port_f (void)
{
	int 	n;

	if (Cmd_Argc () != 2)
	{
		Con_Printf (PRINT_DEFAULT, "\"port\" is \"%u\"\n", net_hostport);
		return;
	}

	n = Q_atoi (Cmd_Argv (1));

	if (n < 1 || n > 65534)
	{
		Con_Printf (PRINT_DEFAULT, "Bad value, must be between 1 and 65534\n");
		return;
	}

	DEFAULTnet_hostport = n;
	net_hostport = n;

	if (listening)
	{
		// force a change to the new port
		Cbuf_AddText ("listen 0\n");
		Cbuf_AddText ("listen 1\n");
	}
}


static void PrintSlistHeader (void)
{
	Con_Printf (PRINT_DEFAULT, "Server          Map             Users\n");
	Con_Printf (PRINT_DEFAULT, "--------------- --------------- -----\n");
	slistLastShown = 0;
}


static void PrintSlist (void)
{
	int n;

	for (n = slistLastShown; n < hostCacheCount; n++)
	{
		if (hostcache[n].maxusers)
			Con_Printf (PRINT_DEFAULT, "%-15.15s %-15.15s %2u/%2u\n", hostcache[n].name, hostcache[n].map, hostcache[n].users, hostcache[n].maxusers);
		else
			Con_Printf (PRINT_DEFAULT, "%-15.15s %-15.15s\n", hostcache[n].name, hostcache[n].map);
	}

	slistLastShown = n;
}


static void PrintSlistTrailer (void)
{
	if (hostCacheCount)
		Con_Printf (PRINT_DEFAULT, "== end list ==\n\n");
	else
		Con_Printf (PRINT_DEFAULT, "No Quake servers found.\n\n");
}


void NET_Slist_f (void)
{
	if (slistInProgress)
		return;

	if (!slistSilent)
	{
		Con_Printf (PRINT_DEFAULT, "Looking for Quake servers...\n");
		PrintSlistHeader ();
	}

	slistInProgress = TRUE;
	slistStartTime = Sys_DoubleTime ();

	SchedulePollProcedure (&slistSendProcedure, 0.0);
	SchedulePollProcedure (&slistPollProcedure, 0.1);

	hostCacheCount = 0;
}


static void Slist_Send (void *junk)
{
	for (net_driverlevel = 0; net_driverlevel < net_numdrivers; net_driverlevel++)
	{
		if (!slistLocal && net_driverlevel == 0)
			continue;

		if (net_drivers[net_driverlevel].initialized == FALSE)
			continue;

		dfunc.SearchForHosts (TRUE);
	}

	if ((Sys_DoubleTime () - slistStartTime) < 0.5)
		SchedulePollProcedure (&slistSendProcedure, 0.75);
}


static void Slist_Poll (void *junk)
{
	for (net_driverlevel = 0; net_driverlevel < net_numdrivers; net_driverlevel++)
	{
		if (!slistLocal && net_driverlevel == 0)
			continue;

		if (net_drivers[net_driverlevel].initialized == FALSE)
			continue;

		dfunc.SearchForHosts (FALSE);
	}

	if (!slistSilent)
		PrintSlist ();

	if ((Sys_DoubleTime () - slistStartTime) < 1.5)
	{
		SchedulePollProcedure (&slistPollProcedure, 0.1);
		return;
	}

	if (!slistSilent)
		PrintSlistTrailer ();

	slistInProgress = FALSE;
	slistSilent = FALSE;
	slistLocal = TRUE;
}


/*
===================
NET_Connect
===================
*/

int hostCacheCount = 0;
hostcache_t hostcache[HOSTCACHESIZE];

qsocket_t *NET_Connect (char *host)
{
	qsocket_t		*ret;
	int				n;
	int				numdrivers = net_numdrivers;

	SetNetTime ();

	if (host && *host == 0)
		host = NULL;

	if (host)
	{
		if (Q_strcasecmp (host, "local") == 0)
		{
			numdrivers = 1;
			goto JustDoIt;
		}

		if (hostCacheCount)
		{
			for (n = 0; n < hostCacheCount; n++)
				if (Q_strcasecmp (host, hostcache[n].name) == 0)
				{
					host = hostcache[n].cname;
					break;
				}

			if (n < hostCacheCount)
				goto JustDoIt;
		}
	}

	slistSilent = host ? TRUE : FALSE;
	NET_Slist_f ();

	while (slistInProgress)
		NET_Poll ();

	if (host == NULL)
	{
		if (hostCacheCount != 1)
			return NULL;

		host = hostcache[0].cname;
		Con_Printf (PRINT_DEFAULT, "Connecting to...\n%s @ %s\n\n", hostcache[0].name, host);
	}

	if (hostCacheCount)
	{
		for (n = 0; n < hostCacheCount; n++)
		{
			if (Q_strcasecmp (host, hostcache[n].name) == 0)
			{
				host = hostcache[n].cname;
				break;
			}
		}
	}

JustDoIt:;
	for (net_driverlevel = 0; net_driverlevel < numdrivers; net_driverlevel++)
	{
		if (net_drivers[net_driverlevel].initialized == FALSE)
			continue;

		ret = dfunc.Connect (host);

		if (ret)
			return ret;
	}

	if (host)
	{
		Con_Printf (PRINT_DEFAULT, "\n");
		PrintSlistHeader ();
		PrintSlist ();
		PrintSlistTrailer ();
	}

	return NULL;
}


/*
===================
NET_CheckNewConnections
===================
*/

qsocket_t *NET_CheckNewConnections (void)
{
	qsocket_t	*ret;

	SetNetTime ();

	for (net_driverlevel = 0; net_driverlevel < net_numdrivers; net_driverlevel++)
	{
		if (net_drivers[net_driverlevel].initialized == FALSE)
			continue;

		if (net_driverlevel && listening == FALSE)
			continue;

		ret = dfunc.CheckNewConnections ();

		if (ret)
		{
			return ret;
		}
	}

	return NULL;
}

/*
===================
NET_Close
===================
*/
void NET_Close (qsocket_t *sock)
{
	if (!sock)
		return;

	if (sock->disconnected)
		return;

	SetNetTime ();

	// call the driver_Close function
	sfunc.Close (sock);

	NET_FreeQSocket (sock);
}


/*
=================
NET_GetMessage

If there is a complete message, return it in net_message

returns 0 if no data is waiting
returns 1 if a message was received
returns -1 if connection is invalid
=================
*/

extern void PrintStats (qsocket_t *s);

int	NET_GetMessage (qsocket_t *sock)
{
	int ret;

	if (!sock)
		return -1;

	if (sock->disconnected)
	{
		Con_Printf (PRINT_DEFAULT, "NET_GetMessage: disconnected socket\n");
		return -1;
	}

	SetNetTime ();

	ret = sfunc.QGetMessage (sock);

	// see if this connection has timed out
	if (ret == 0 && sock->driver)
	{
		if (net_time - sock->lastMessageTime > net_messagetimeout->value)
		{
			NET_Close (sock);
			return -1;
		}
	}


	if (ret > 0)
	{
		if (sock->driver)
		{
			sock->lastMessageTime = net_time;

			if (ret == 1)
				messagesReceived++;
			else if (ret == 2)
				unreliableMessagesReceived++;
		}
	}

	return ret;
}


/*
==================
NET_SendMessage

Try to send a complete length+message unit over the reliable stream.
returns 0 if the message cannot be delivered reliably, but the connection
		is still considered valid
returns 1 if the message was sent properly
returns -1 if the connection died
==================
*/

int NET_SendMessage (qsocket_t *sock, sizebuf_t *data)
{
	int		r;

	if (!sock)
		return -1;

	if (sock->disconnected)
	{
		Con_Printf (PRINT_DEFAULT, "NET_SendMessage: disconnected socket\n");
		return -1;
	}

	SetNetTime ();
	r = sfunc.QSendMessage (sock, data);

	if (r == 1 && sock->driver)
		messagesSent++;

	return r;
}


int NET_SendUnreliableMessage (qsocket_t *sock, sizebuf_t *data)
{
	int		r;

	if (!sock)
		return -1;

	if (sock->disconnected)
	{
		Con_Printf (PRINT_DEFAULT, "NET_SendMessage: disconnected socket\n");
		return -1;
	}

	SetNetTime ();
	r = sfunc.SendUnreliableMessage (sock, data);

	if (r == 1 && sock->driver)
		unreliableMessagesSent++;

	return r;
}


/*
==================
NET_CanSendMessage

Returns TRUE or FALSE if the given qsocket can currently accept a
message to be transmitted.
==================
*/
BOOL NET_CanSendMessage (qsocket_t *sock)
{
	int		r;

	if (!sock)
		return FALSE;

	if (sock->disconnected)
		return FALSE;

	SetNetTime ();

	r = sfunc.CanSendMessage (sock);

	return r;
}


int NET_SendToAll (sizebuf_t *data, int blocktime)
{
	double		start;
	int			i;
	int			count = 0;
	BOOL	state1 [MAX_SCOREBOARD];
	BOOL	state2 [MAX_SCOREBOARD];

	for (i = 0, host_client = svs.clients; i < svs.maxclients; i++, host_client++)
	{
		if (!host_client->netconnection)
			continue;

		if (host_client->active)
		{
			if (host_client->netconnection->driver == 0)
			{
				NET_SendMessage (host_client->netconnection, data);
				state1[i] = TRUE;
				state2[i] = TRUE;
				continue;
			}

			count++;
			state1[i] = FALSE;
			state2[i] = FALSE;
		}
		else
		{
			state1[i] = TRUE;
			state2[i] = TRUE;
		}
	}

	start = Sys_DoubleTime ();

	while (count)
	{
		count = 0;

		for (i = 0, host_client = svs.clients; i < svs.maxclients; i++, host_client++)
		{
			if (!state1[i])
			{
				if (NET_CanSendMessage (host_client->netconnection))
				{
					state1[i] = TRUE;
					NET_SendMessage (host_client->netconnection, data);
				}
				else
				{
					NET_GetMessage (host_client->netconnection);
				}

				count++;
				continue;
			}

			if (!state2[i])
			{
				if (NET_CanSendMessage (host_client->netconnection))
				{
					state2[i] = TRUE;
				}
				else
				{
					NET_GetMessage (host_client->netconnection);
				}

				count++;
				continue;
			}
		}

		if ((Sys_DoubleTime () - start) > blocktime)
			break;
	}

	return count;
}


//=============================================================================

/*
====================
NET_Init
====================
*/

void NET_Init (void)
{
	int			i;
	int			controlSocket;
	qsocket_t	*s;

	i = COM_CheckParm ("-port");

	if (!i)
		i = COM_CheckParm ("-udpport");

	if (!i)
		i = COM_CheckParm ("-ipxport");

	if (i)
	{
		if (i < com_argc - 1)
			DEFAULTnet_hostport = Q_atoi (com_argv[i + 1]);
		else
			Sys_Error ("NET_Init: you must specify a number after -port");
	}

	net_hostport = DEFAULTnet_hostport;

	if (COM_CheckParm ("-listen"))
		listening = TRUE;

	net_numsockets = svs.maxclientslimit;

	// add an extra socket for loopback
	net_numsockets++;

	SetNetTime ();

	for (i = 0; i < net_numsockets; i++)
	{
		s = (qsocket_t *) zoneHeap->Alloc (sizeof (qsocket_t));
		s->next = net_freeSockets;
		net_freeSockets = s;
		s->disconnected = TRUE;
	}

	// allocate space for network message buffer
	SZ_Alloc (&net_message, NET_MAXMESSAGE);

	net_messagetimeout = Cvar_Get ("net_messagetimeout", "300");
	hostname = Cvar_Get ("hostname", "UNNAMED");

	Cmd_AddCommand ("slist", NET_Slist_f);
	Cmd_AddCommand ("listen", NET_Listen_f);
	Cmd_AddCommand ("maxplayers", MaxPlayers_f);
	Cmd_AddCommand ("port", NET_Port_f);

	// initialize all the drivers
	for (net_driverlevel = 0; net_driverlevel < net_numdrivers; net_driverlevel++)
	{
		controlSocket = net_drivers[net_driverlevel].Init ();

		if (controlSocket == -1)
			continue;

		net_drivers[net_driverlevel].initialized = TRUE;
		net_drivers[net_driverlevel].controlSock = controlSocket;

		if (listening)
			net_drivers[net_driverlevel].Listen (TRUE);
	}

	if (*my_ipx_address)
		Con_Printf (PRINT_DEVELOPER, "IPX address %s\n", my_ipx_address);

	if (*my_tcpip_address)
		Con_Printf (PRINT_DEVELOPER, "TCP/IP address %s\n", my_tcpip_address);
}

/*
====================
NET_Shutdown
====================
*/

void NET_Shutdown (void)
{
	qsocket_t	*sock;

	SetNetTime ();

	for (sock = net_activeSockets; sock; sock = sock->next)
		NET_Close (sock);

	// shutdown the drivers
	for (net_driverlevel = 0; net_driverlevel < net_numdrivers; net_driverlevel++)
	{
		if (net_drivers[net_driverlevel].initialized == TRUE)
		{
			net_drivers[net_driverlevel].Shutdown ();
			net_drivers[net_driverlevel].initialized = FALSE;
		}
	}
}


static PollProcedure *pollProcedureList = NULL;

void NET_Poll (void)
{
	PollProcedure *pp;

	if (!configRestored)
	{
		configRestored = TRUE;
	}

	SetNetTime ();

	for (pp = pollProcedureList; pp; pp = pp->next)
	{
		if (pp->nextTime > net_time)
			break;

		pollProcedureList = pp->next;
		pp->procedure (pp->arg);
	}
}


void SchedulePollProcedure (PollProcedure *proc, double timeOffset)
{
	PollProcedure *pp, *prev;

	proc->nextTime = Sys_DoubleTime () + timeOffset;

	for (pp = pollProcedureList, prev = NULL; pp; pp = pp->next)
	{
		if (pp->nextTime >= proc->nextTime)
			break;

		prev = pp;
	}

	if (prev == NULL)
	{
		proc->next = pollProcedureList;
		pollProcedureList = proc;
		return;
	}

	proc->next = pp;
	prev->next = proc;
}

